The present invention relates to a lens holder for an apparatus for grinding the edges of a lens. The lens holder includes two coaxial, rotatable shaft halves that have adjacent ends between which the lens is held, with one of the shaft halves being axially shiftable to permit insertion, securing, and removal of the lens.
Lens holders of this general type are known. With such holders, securing of the lens is effected via pressure medium, with a pressure-relief valve being provided via which, during feeding or advancement of the axially adjustable shaft half, the latter is subjected to a weaker pressure until it rests against the lens. For the final securement of the lens, which is subjected to a radial grinding pressure during the grinding process, a greater pressure can be exerted upon the axially adjustable shaft half. If with this heretofore known lens holder the greater pressure is inadvertently applied before the free end of the axially adjustabIe shaft half rests against the lens, the danger exists that this shaft half, at high pressure, will strike either the lens, which is not yet in the proper position between the two shaft halves, or one or more fingers of the operator. It is an object of the present invention to provide a lens holder that avoids these drawbacks with structurally straightforward means .